This invention relates to the pipeline maintenance art and, more particularly, to apparatus for handling a pipeline scraper.
Pipeline scrapers are periodically (more often in the summer than in the winter) introduced into pipelines to be conveyed, along with the transported fluid, through the pipeline from one pump station to the next. These scrapers (sometimes called "pigs") serve to remove coatings of paraffin and other undesirable material from the inner walls of the pipeline in order to maintain its capacity and efficiency. It is notoriously well understood, by those skilled in the art, that, upon reaching an exit position, the scraper is remarkably messy and, as such, is difficult and disagreeable to handle. Before being reintroduced into the line for cleaning the section of pipe to the next pump station, the scraper must be cleaned, usually by boiling it in a vat.
While handing small scrapers is not a particularly difficult task, and can be carried out manually, those skilled in the art appreciate that scrapers may be as large as sixty inches in diameter and, with an accumulated load of paraffin and the like, may weigh several hundred pounds. Handling of large scrapers has generally been carried out manually by using local hoists at the receiving and launching traps and at the vat site in conjunction with a general purpose truck or trailer to effect transportation.
Thus, those skilled in the art will appreciate that it would be highly desirable to provide means for efficiently receiving, transporting, cleaning, and launching a scraper while avoiding, to a considerable extent, the heavy labor and extra-ordinary mess ordinarily associated with this task.
It is therefore a broad object of my invention to provide improved scraper handling means.
It is another object of my invention to provide such scraper handling means which can readily accomodate the different heights of incoming and launching traps.
It is a more particular object of my invention to provide such scraper handling means which comprises a unitary vehicle having a height-adjustable cradle for receiving, transporting, and launching a scraper and which further provides for easy access to the cleaning vat using a single hoist.